Hi Richard
There's a bit of confusion here, caused by people who should have known better; some years ago the term 'stain' was suddenly adopted by the exterior coatings industry to mean a coloured microporous coating which gave a finish and coloured at the same time. Something which was used only to colour wood was called a 'dye'. I don't know why this happened and it wasn't something I subscribed to. These terms were only (to my knowledge) used widely in the retail/DIY market whereas the trade used the terms interchangably. Very confusing!
So...
Our Spirit Stain is suitable for use outdoors as it is very fade resistant but should only be used on bare wood. However, it will only colour the wood and will need a coating over the top of it to seal it in and to protect the wood. (The pigments used are also soluble in water and rain will eventually wash it off if it can make contact with it).
If you are working on new wood I'd suggest either Finishing Oil which will seal the stain in and protect the wood and give easy maintenance or one of our Acrylic Aerosol lacquers; these are very hardwearing, have a UV filter and will withstand most weathering.
It would be helpful to know a little more about the project you are undertaking to double check that this is the right advice; it might be that these finishes are 'over the top' for what you are doing (for example, I wouldn't use these on a fence as it would be too hard to do! I'm guessing we're not talking about a fence here but I'm sure you get what I am trying to say)